Illumination louver



March 27, 1951 J. R. FRIEND ILLUMINATION LOUVER Filed March 28, 1949 INVEN TOR, IJHMES 2. FP/EIND.

Patented Mar. '27, 1951 e 1 UNI TED "S TAT-ES ATENT' ()FFICE ILLUMINATION LOUVER- James R. Friend, Rolling Hilla calif.

I AppIicatiUnMarchZS, 1949,8erialNo583l795 This invention relates to an illumination louver designed -to be used in the ceilings of schoolrooms, exhibition rooms, and thelike.

A primary object of the invention is to provide a louver, the louver boards of which are stationarily mounted inasmuch as they do not require adjustment and which will .receive incident sunlight through a skylight or the like and reflect thelight downwardly into the room in a dispersed ordistributedmannerso that that portion-of the room beneath the louver .will .be adequately illuminated with evenly distributed light.

More specifically, an object 'of the invention .is to provide an illumination louver .having the above mentioned characteristics which is. so designed :as to properly function throughdifferent seasons and which is ;so designed that lit .canbe easily and economically manufactured and installed.

With the foregoing and other'objects in View, which will be made manifest in the following detailed description and specifically pointed out in .thelappended claims, referenceishad to the accompanying drawings for an illustrative -embodiment of the invention,whereinz Figure v1.is .a top plan view of a schoolroom, the ceiling bein illustrated as having been removed except at the location of the louver embodying the present invention;

Fig. 2 is a vertical section taken substantially upon the line 2-2 upon Fig. .1;

"Fig. 3'is a transverse section through a pair of louvers illustrating diagrammatically the manner in which the light is reflected during spring and .fall seasons;

Fig.4 is 'a similar view illustrating diagrammatically the manner in whichthe light is reflected when the sunlight :has its minimum inclination; and

Fig.5 isa similar view-illustrating diagrammatically a condition wherein the sunlight has its maximum inclination.

Referring to the accompanying drawings wherein similar reference characters designate similar parts throughout, the reference character H3 indicates generally a schoolroom which is taken as a typical illustration of the manner in which the improved louver can be advantageously employed. The louver embodying the present invention is in no way restricted inzits use to schoolrooms but maybe employed in any room where an adequate distributionof reflected light is desired. .In the schoolroom illustrated abank of windows ,H has been shownlin .one

.4 Claims. ,(01. sag-. 575).

wall thereof which-maybe assumed'to adequately illuminate desks or tables adjacent that wall.- The opposite wall indicated at 1-2 however has been shown as havin no windows therein "so that, in the absence of any correcting means,

the space adja'cent the -wall L2 willbe relatively dark. The roof or-ceil-ing of the room is indi-L cated at 13 and has therein a skylight l Lo'f any conventional or preferred design which is die-' signed to admit light 2.to the .room over that portion "thereof which is adjacent the wall k2;- While sunlightcouldbe permitted to-enterzthe room'throug'h the skylight M, the use :ofldirect lengths of .theiouver boards extend in .a north-..; south direction. Each .louver board may i'bQ regarded as *b'ein g'icurved in, a transverse direct-.1 tion and is somewhat :thinner adjacent :itslower; edge thannear its top. The under side .of reach louver :bo'ard is convexly curved as :indicatediat,

ltwith the inclination of this curvature gradually increasing from the bottom edge .of the board upwardly so that near :the top .of-theeunder surface .of the :board thesurf-ace is inclined .-.to;; the horizontal to .a greaterextentthanit isead jacentthe bottom edgeof the-board. Theupper surface of each board is generally concave and is so formed by three contiguous flat surfaces being indicated at 1-1, 1.8, and E9. The inclinetions of these ,surfaces to the horizontal .pro:- gressively increase from the lowermost surface; I? to the uppermost-surface 19. Thus, as illustrated, the inclination of the surface I .1 isapproximately 515 to the horizontal, the inclination of -the surface J8 is approximately ,and the surface l9 closely approaches, but is not; perfectly, vertical. The top edge of the board; is beveled ofi as .at :20, the bevel :being .approxi-f mately 60 to .the horizontal.

The .boardsare spaced from each other so that} the vertical projection of one-board is butslightly; spaced from the vertical projectionof-adjacent,

boards.

The improved louver is .designed to .be under all conditions pf r sunlight throughout the;

year without requiring any adjustment. Some slight modification or adjustment of the shaping of the louver boards may be necessary in different latitudes. However, by way of illustration in the latitude of Los Angeles, California, the minimum inclination of sunlight in the winter is approximately 32 /2 whereas the maximum inclination during the summer is approximately 79. Figure 4 illustrates sunlight encountering the louver boards during the winter wherein the incident light from the sun has an inclination to the horizontal of approximately 32 /2. Under these circumstances the incident light will encounter the concave side of each louver board against the uppermost surface and only a portion of the surface l8. That portion of the light which encounters the surface l8 has an angle of incidence thereto of approximately 90 so that much of this light will be reversely reflected thereby as indicated by the arrow 2|. That light which encounters the surface l9 will be reflected thereby over the under surface 16 of the adjacent board which, due to its convexity, will reflect the light downwardly into the room with considerable dispersion so as to distribute the light from the wall I2 over approximately one-half of the room.

In the other extreme condition illustrated in Fig. 5, the incident light encounters the louver boards at an angle of approximately 79 to the horizontal. This incident light reaches all three surfaces 19, I8, and I1 and is reflected thereby against the under side I6 of the adjacent louver boards. This surface reflects the light downwardly and due to the convexity causes considerable dispersion as is illustrated diagrammaticaliy in this figure. In the intermediate condition, which is illustrated in Fig. 3, the incident light encounters the louver boards at an angle to the horizontal which is between the two extreme conditions depicted in Figs. 4 and 5. Thus, as illustrated in this figure the light may encounter the entire surface IS, the entire surface l8, and a portion of the lower surface 11. The light reflected from the upper surface is may be reflected thereby into the room without being reflected by the surface l6. That light which is reflected by the surface IE will be reflected thereby against the surface l6 and reflected thereby downwardly into the room with some dispersion due to the convexity of the under surface Id. That light which encounters the surface I! may be reflected back and forth several times between the surface l1 and the surface IE but will ultimately be reflected by the surface 16 downwardly into the room with considerable dispersion.

It will be appreciated from the above-described construction that the improved louver never permits direct sunlight to pass through the skylight l4 and directly into the room but that the light is always reflected at least once. Most of the light that encounters the upper surface of a louver board will be reflected thereby onto the under surface l6 of the adjoining board which is so arranged as to reflect the light downwardly and to disperse or distribute it. It will, of course, be appreciated that in different latitudes that the maximum and minimum inclination of the sunlight which is incident to the louver will vary and that slight changes in the exact inclinations of the surfaces l1, I8, and I9 and of the curvature of the surface I6 may be necessary in order to have the louver operate to the best advantage. While it would be possible to form the upper surfaces of the boards in the form of a smooth transverse curve similar to the curve Hi, the use of contiguous flat surfaces ll, l8 and I9 is preferable from the manufacturing standpoint in that it is relatively easy to give the board the shaping illustrated with conventional woodworking machines, it being unders.ood that these louver boards are generally formed of wood.

From the above described construction it will be appreciated that the improved illumination louver can be easily and economically manufactured and installed and that when installed the louver boards may remain stationary. However, they are so designed as to automatically receive and reflect light into the room under all conditions from the extreme in winter to the extreme in summer. That light which is reflected into the room is adequately disersed or spread over a sufficient portion of the room as to adequately supplement the lighting available through the windows II.

Various changes may be made in the details of construction without departing from the spirit and scope of the invention as defined by the appended claims.

I claim:

1. An illumination louver having a series of substantially parallel opaque louver boards each of which is transversely inclined and which is characterized by having on the upper sides thereof a series of contiguous fiat surfaces progressively increasing in inclination from bottom to top and having on the under sides thereof convexiy curved surfaces arranged to receive light reflected from the flat surfaces and reflect downwardly with dispersion.

2. An illuminating louver having a series of substantially parallel louver boards, each of which is transversely inclined and which is characterized by having on the upper side thereof a series of three or more contiguous flat surfaces progressively increasing in inclination from bottom to top and having on the under side thereof a convexly curved surface arranged to receive light reflected from the flat surfaces and reflect downwardly with dispersion.

3. An illuminating louver for conducting sunlight into a room comprising a series of substantially parallel louver boards arranged in a' generally east to west direction, each of the boards being transversely inclined and being characterized by having on the upper side thereof a series of at least three contiguous flat surfaces progressively increasing in inclination from bottom to top and having on the under side thereof a convexly curved surface extending from the bottom edge upwardly through a major portion of the width of the boards, each board having a flat bevel at its top connecting the top of the convex surface with the top of the upper- 4. An illumination louver having a series ofsubstantially parallel louver boards each of which is transversely inclined and which is characterized by having on the upper sides thereof a series of three or more contiguous flat surfaces progressively increasing in inclination from bottom to top and having on the under side thereof a convexly curved surface arranged to re- 5 t ceive light reflected from the flat surfaces and reflect downwardly with dispersion, the louver N 10' boards being characterized by increasing in thick- 3 5 ness from their lower edges upwardly. 721:258 5 1:247928 JAMES R. FRIEND. 2,276,425 2,300,545

REFERENCES CITED The following references are of record in the 10 Number file of this patent: 20,046 185,914 

